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Psychiatric Disorders/childhood disorders/Pharmacotherapy

Prior to a discussion of pharmacotherapy it is prudent to discuss the decision-making process around the use of medication, especially given the rapid advances in this area and the array of medications now available. Whilst in some centers there is easy access to senior colleagues for advice, as a default strategy this is generally unsustainable and clearly does not work in regional hospitals or rural and remote settings. To this end practitioners need to be adept at accessing contemporary clinical practice guidelines from professional organizations (e.g. N.I.C.E.), Cochrane reviews, other published meta analyses and systematic reviews. Pharmacotherapy texts are often very informative, so too formularies that are often produced by government bodies; albeit care is required as some information can become out of date. The technology age has also made long distance communication available to many and so advice via email or phone can be obtained even if geographically remote. On-line discussion groups are also becoming more popular.

If these strategies do not provide the answer required then one should consider the conclusions of a seminal study in the area. Prior to accepting the findings of a seminal study the practitioner should determine whether the study is methologically sound, has sufficient power, both genders and a range of ethnicities and social economic groups are included as participants thereby allowing generalization of findings into various practice settings. Finally, conclusions should be conservative in that they are consistent with the rigour of the methodology and strength of the analysis.

Various authors have published psychopharmacology practice advice relevant to children and adolescents. The over-arching principle is that medication prescription should only follow an adequate assessment and formulation. A broad formulation will determine whether there are ongoing causal or maintaining factors within the family system or local ecology. Many practitioners find the ‘predisposing, precipitating and perpetuating factor’ heuristic helpful. An example being one should not prescribe medication for anxiety if the child is still being physically abused. In this case the treatment is to facilitate the provision of a safe environment. A prescribing generalisation is to start with a low dose. Child and parent compliance can be radically undermined by early adverse side-effects and so slowly increasing medication dose at the same time as predicting typical adverse events is prudent. Whenever possible dosage regimes should be dependent on the child's weight. There are adequate milligrams (drug) per kilogram (child weight) dosage schedules for stimulant medication, some atypical psychotics, tricyclic antidepressants such as Clomiprame for OCD and Sodium Valproate. Once a decision to prescribe is undertaken then the medication trial should continue, with regular monitoring, until an adequate dose has been trialed for an adequate period of time. Premature cessation creates uncertainty as to whether a certain medication is beneficial or not. If available and there are no financial constraints, new medications are preferable especially given their greater safety profile and fewer side-effects. Good prescribing needs to consider whether there are physical factors that influence the bioavailability of the medication such as concurrent liver or renal disease and in the patient with epilepsy some medications, especially anti-psychotic medication, can lower the fit threshold. Drug-drug interactions can occur, especially when drugs are combined which both affect these same neurotransmitter pathway.

When practicing child and adolescent psychiatry or behavioural paediatrics, there can be pressure from parents or teachers to increase medication dose beyond the usual parameters or too prescribe additional medications to obtain symptom control. This can be a serious problem in the overall management of the case. Family dysfunction including arguments between parents or the threat of school suspension is not a valid reason to increase the child's medication. There are persuasive research findings, for instance in the area of ADHD, that combining psychological interventions with medication is associated with lower medication dose. One assumes combined therapy can also decrease the number of medications required. Symptom deterioration is a reason to (a) review the diagnosis, (b) review barriers and maintaining factors, (c) look for new causal factors (d) review your therapeutic alliance with the child and family and (e) to consider comorbidity. The latter may be secondary to the original presentation, for instance a depressive illness in a teenager struggling with chronic anorexia nervosa. When these factors have been accounted for then increasing the dose or considering a second medication is reasonable. The prudent practitioner will also decide upon a small selection of medications with which they become very familiar with and prescribe preferentially. Use of a small number of medications allows greater knowledge of the typical dosage regime, side-effects and interaction profiles and also allows the practitioner to prepare and have ready access to patient information handouts.